High tension circuit interrupter



Aug. 16, 1932. w. H. TURNPENNY HIGH TENSION CIRCUIT INTERRUPT'ER Filed Nov. 25', 1930 2 Sheets-Sheet l 'p'enhg,

His Abto'vneg Inventor": William HTur'h u i. 9 w. H. TURNPENNY 1,372,530

HIGH TENSION CIRCUIT INTERRUPTER Filed Nov. 25, 1930 2 Sheets-Sheet 2 Fig.3. I

Inventor: Wll |iam H. Tur'n'pe'nhg,

His Abpo'i neg;

Patented Aug. 16, 1932 .umrso sir-Ares PATENT OFFICE v WILLIAM H. TURNPENNY', OI ALI BANY, NEW YORK, ABSIGNOR TO GENERAL ELECTRIC OOMPANY, A CORPORATION OF NEW YORK HIGH TENSION CIRCUIT INTERBUPTfl Application filed November 25, 1830. Serial No. 498,075.

My invention relates to high tension circult interrupters of the fluid-break ty e, and more particularly to',the explosion c amber type wherein an initial or pressure generatmg are is utilized to effect a blast of oil or other insulating liquid through and across the main are for interrupting the circuit.

One of the major problems in interrupting high tension circuits, as of the order of 132 kv. or more, is that of preventing flashover in the circuit interrupting apparatus during interruption of high tension are. In man cases, the insulating structure for the switc contacts has failed with the result that the'arc isshorted to parts of the apparatus other than the normal contact surfaces, so that failure of the switch generally results.

It is a principal object of my invention to I provide an improved high tension circuit interrupter wherein the current carrying parts are effectively insulated so that flashover during circuit interruption is substantially preeluded.

It is a further. object of my invention to.

provide an improved high tension circuit interrupter of the character above referred to which shall have comparatively few parts and be simple and rugged in construction and which may be easily assembled and inspected.

Myinvention will be more fully set. forth in the following description referring-t the accompanying drawings, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

Referring to "the drawings, Fig. 1 is an elevational view, partly in section, of high tension circuit interrupting apparatus embodying my invention; Fig. 2 is a plan view taken alongthe line 22 of Fig. '1, Fig. 3 is an elevational view, partly in section, of a similarform of circuit interrupting apparatus likewise embodying my invention and Fig. 4.- is a plan View taken along the line 44 of Fig. 3.

In Fig. 1 there is shown a single pole of a high tension circuit interrupter of the fluid-break explosion chamber type comprising an explosion chamber member or pot 1 constructed entirely of insulating material secured at its flanged end wall 1-,- as b the clamping ring 3 and bolts 4, to the perip eral flange portion 5 of the metallic adapter 6 constituting the supportingstructure for the switch contact structure. The adapter 6 is. clamped in a well known manner to the lower end of the lead-in insulator 7 through which the conductor stud connected to the adapter extends.

For the purpose of simplicity but a single ole of the circuit. interrupter is shown, it eing of course understood that the insulator 7 may be mounted in the usual manner in the top of a steel tank containing oil within which the circuitinterrupting apparatus is immersed.

The insulating explosion chamber member 1 is constructedto withstand high internal pressures, and preferably is of the construction disclosed in a co ending application Serial No. 358,072, filed April 25, 1929, by Charles F. Petersen for method and apparatus for making laminated insulation explosion chamber members, and assigned to thesame assignee as the present invention.

The upper or contact supporting side of the explosion chamber comprises a plate-like member 8 secured in any suitable manner as by bolts to the lower plane side of the adapter 6. The plate member 8 in the present instance comprises a metallic casting or alloy and is provided with lateral flanges 8 having apertures through which bolts may extend to clamp the same to the adapter 6. It shall be understood, however, that the plate member 8 may if desired be constructed of strong insulating material.

The switch contact structure comprises a butt contact 9 of brass or other suitable arcresisting material mounted and guided for reciprocal movement within a centrally disposed aperture in the plate member 8 and biased, as by a spring 10, towards a lower limiting position with respect to the plate. The aperture for the contact 9 includes a flared opening 11 formed in the plate 8 within which the contact extends. When the plate 8 is of metal the lower edge of this opening serves as an arcing tip in the event that the contact 9 is forced in a manner hereinafter described upwardly far into the opening 11. A positioning and guide tube 12 encloses the spring 10 and is detachably mounted, as by screw-threaded engagement, to the plate member 8. The tube 12 is likewise slotted at 13 to permit extension therethrough of the flexible conductors 14 which are suitably connected to the'butt contact 9 and to the plate 8, or to the adapter 6 in case the plate 8 is of insulation.

Coacting with the butt contact 9 within'the explosion chamber is a floating contact 15 likewise of brass or the like including upper and lower butt contact surfaces for engaging respectivelythe contact 9 and a rod contact ing fibre material.

16 operable to extend within the explosion chamber. The floating contact 15 is'carried by an insulating disk17 of fibre or'other strong insulating material which is in turn supported by a pair of insulating pins 18 mounted and guided for reciprocal movement within the plate member 8 and provided with stops members 18 coacting therewith. The insulating guide pins, 18 may extend on opposite sides of the contact 9 and preferably are constructed of strong insulat- Each of the guide'pins 18 is biased by a spring 19, 'mountedwithin and bearing against the upper end of a positioning and guide tube 20, so that the floating contact 15 is biased downwardly and away from the contact 9 in the open position illustrated in Fig. 1. The tubular butt contact 16, which is provided with a removable material, and a pressure'relief vent 22, is operable to move in a vertical direction-through the throat opening 23 of the explosion chamber member to abut one end of the floating contact 15 and to force it, against e bias of the springs 19, into engagement with the butt contact 9, thereby'completing the circuit from the adapter. 6 to the movable rod contact 16. The contact structure in the position illustrated in Fig. 1 may be considered as in the partly closed position wherein the contact rod 16 in its upward movement has engaged the floating contact so that further closing movement causes the floating contact to be moved against the bias of the springs 19 into engagement with contact 9.

The switch opening operation is performed by lowering the rod contact 16, which may be connected in the usual manner to a bridgw ing member and operating rod within the switch tank. The spring 10 acting on the butt contact 9 permits a certain amount of overtravelof the movable contact rod so that the coacting butt contact surfaces are each resiliently urged into engagement with each other at substantially constant contact. pressure. Therefore, upon downward movement of the rod 16, the contacts 9 and 15 are extending tend to remain in limited followin engagement until the shoulder 9 of 16%)11? con tact 9 engages the plate member 8. At this point an arc isdrawn between the floating contact 15 and. the butt contact 9 due to the fact that the floating contact 15 is still in following engagement with the rod 16. This initial or pressure generating arc causes dc composition ofthe oil within the explosion chamber a'nd'formation of gases at a high rate so as to developehigh pressure within the explosion cham, r. This pressure is mainly confined in the explosion chamber by the rod 16 until the floating contact 15 reaches its lower limit" ofmovement thereupon causing the rod 16 to separate therefromand draw a second'arc between the same and the floating contact. When this occurs the end of the tubular contact 16 is uncovered so that the pressure within the explosion chamber is effective to direct a blast of oil contact to-exhaust exteriorly of the chamber through the vent 22. It will, therefore, be apparent that the pressure generated by the initial arc maybe directed so as to extinguish a main arc in series therewith by literally washing the are into the tubular contact before it everf leaves the explosion chamber. For the purpose of permitting oil completely to fill the explosion chamber after a circuit interruption, the upper part of the chamber is provided with a vent 5' through which entrapped gas may escape.

It will be noted that the arrangement of -the' floating contact supporting disk 17 tocontact tip 21 of brass or other arc-resisting gether with the insulating guide pins 18 within the insulating explosion chamber 1 effectively insulates the contacts so that flashover between the stationary and movable conducting switch structure is improbable. In the present instance, the floating contact is solinsulated that-shorting thereof by an directly between the upper butt contact and the movable rod contact is precluded. Y

The apparatus may likewise be provided with the usual cylindrical insulating shield 24 mounted at its lower end in any suitable manneron the supporting ring 25 of wood or the like secured to the clamping ring 3.

In a preferred modification shown in Fig. 3 the adapter structure and the plate member forming the upper part of the explosion insulating fibre material which is clamped, as by, the bolts 28 and the clam ing ring 28', between the flange 29 of the ad apter 30 and the peripheral flange 31 of the explosion chamber member. Accordingly, the adapter 30 serves both to support the explosion chamber structure as a unit and to osition the insulating plate 27. The cylindrical insulating shield 32 is mounted, as in the previous instance, at its lower end on a supporting ring 33 composed of wood or other suitable material, the ring 33 being secured as by bolts (not shown) to the rings 28. A supporting ring 34, likewise of 'wood or similar insulating material, is suitabl mounted on the adapter30 for bracing t e insulating shield 32 with respect to lateral movement.

The adapter 30 has formed therein an inverted cup-shaped recess 35 disposed above the insulating plate 27 and serving as a housing for certain parts of the contact structure.

A butt contact 36 having a flexible connection 36 suitably connected to the ada ter 30 and a shoulder portion 37 is carrie by the plate 27 and extends through a flared aperture 38 therein. The contact 36 is biased, as by spring 39, towards a limiting position wherein the shoulder 37 engages plate 27, an adjustable pin or stop 40 mounted in the adapter 30 serving both to position the spring 39 and to limit upward movement of the contact 36 in a manner hereinafter described. The plate27 and the adapter 30 are likewise provided with vents 41 so that no gas pockets may form preventing oil from refilling the chamber after a circuit interruption.

The floating contact 42 mounted on and carried by the insulating disk 43 is similar in construction and arrangement to that previously described, the plate 43 being carried by a plurality of strong insulating pins 44, circumferentially arranged and extending through apertures in the plate 27 For the purpose of spacing the pins 44 as far as possible from the arc in order to prevent or minimize carbonization of the insulating material by the arc, the disk 43 is provided with projections as illustrated in Fig. 4 in which the pins are mounted. This arrangement allows suflicient passage between the up r and lower compartments of the exploslon chamber while removing the insulating supporting pins from the vicinity of the arc. Accordingly, the effect of creepage, due to carbonization, is greatly minimized.

Each guide pin is provided with a collar 45 limiting the downward movement of the pin under the influence of the spring 46. The

tubular contact rod 47 is in general similar to contact rod 16, the only difference being in the arrangement of the pressure relief vents 48 and the screw-threaded portion 49 for securing the same to the bridging member. The operation of the.circuit interrupter shown in Fig. 3 is substantially the same-as for the fact that the stop member 40 limits the popback action of the, butt contact 36 i in responseto the initial arcing pressure.-

It shell, of course, be understood that the, i

stop 40 is adjustable so that the "lengthening of the initial pressure generating. arc may be limited to a ver small amount, thereby insuring substantia ly constant length and constant pressure of the initial arc. 4

It will furthermore be noted that the heavy insulating plate 21 eliminates all conducting material in the region of theswitch contacts so that there is practically no possibility for the arc to shift-or strike from the contact rod to conducting parts other than the switch contacts. Due to the fact that the initial pressure generating arc is quite short and practically constant in length, it will have little tendency to shift whereas the 'main are drawn between the floating contact and the contact rod is so far removed from other conductin parts of the apparatus that flashover is substantially precluded. The resulting se aration of the tubular contact rod from t e floating contact near the lower end of the explosion chamber within a body of oil insures a blast of comparatively cool oil across and through the are into the tubular contact. The gases generated by the initial are are in general confined to the space in the chamber above the insulating disk carrying the floating contact so that these gases are not mixed'to any appreciable extent with the oil directed across the main arc.

The shape of the insulating disk carrying the floating contact may assume various forms, a limiting factor being the relation of' its area, for certain interrupting capacities, with respect to the internal cross sectional area of the explosion chamber at that particular position. In other words, there must be snflicient passage around the edge of the disk efliciently to transmit the pressure to the main arc while reventing union of the gas bubbles formed y the pressure generating and main arcs. As is well known, the gas bubble formed in the oil by the arc is a very good conductor so that mingling of the gas bubbles within the explosion chamber would in all probability short the are around the floating contact and thereby defeat the purpose of the same.

Accordingly, the communicating passage from the pressure generating chamber, i. e;

the space above the floating contact disk in It shall lie understood that my invention is not limited to specifi c details of construction and arrangement thereof herein illustratedfand that changes and modifications may occur to one skilled; in the art without depgrting from the spirit of myinvention.

- supporting structure, a contact supporting member forming one side of said explosion chamber, a pair of coacting contacts carried by and resiliently mounted with respect to said supporting member for reciproca movement, and a relatively movable rod contact extending within said explosion chamber for completing the circuit.

2. A high tension circuit interrupter of the fluid-break type comprising supporting.

structure, an explosion chamber pot of insulating material secured to said structure, a member forming one side of said explosion chamber, a butt contact mounted in said member, a relatively movable floating contact coacting with said butt contact within said chamber, an insulating supporting disk for said floating contact, said disk being guided for reciprocal movement with respect to said butt contact by insulatin guides, and a rod contact operable to extend within said chamber and abut said floating contact. L

3. A high tension circuit interrupter of the fluid-break type comprising an explosion chamber pot of. insulating material adapted to withstand high internal pressures, a member of insulating material formin one side of said explosion chamber, means or clamping said memher to said explosion chamber .pot and for supporting the same, a butt contact mounted in said insulating member, a floating contact carried by said insulating member, and a coacting contact operable to engage said floatin contact and to bias it into engagement wit said butt contact.

4. A high'tension circuit interrupter of the fluid-break t e comprisin a lead-in insulator, an ad a pter of con ucting material clampigd to the lower end of said insulator, said adapter having a peripheral flanged portion, an ex losion chamber pot of insulating material a apted to withstand high internal pressures, said pot likewise having a flanged peripheral portion, a plate of insulating material forming the upper side of said explosion chamber, a pair of relatively movable contacts carried by said plate, clamping means for securing in position said plate between the flangedportions of said adapter fluid-break type comprising an explosion chamber. poto insulating material adapted to withstand high internal pressures, a member forming the upper side of said chamber,

an adapter with respect to which the explosion chamber structure is mounted, a butt contact mounted in said member, a coacting floating contact mounted on an insulating with said butt contact in the closed circuit position.

6; A hi h tension circuit interrupter of the fluid-brea type comprising an explosion chamber pot of insulating material adapted to withstand .high internal pressures, an adapter of conducting material to which the explosion chamber structure is secured, a plate member formin the upper side of said chamber and secure to said adapter, an arcing portion'on said plate member, a butt contact mounted for reciprocal movement within said plate member, a floatin contact coacting with said butt contact wit in said chamber, said floating contact carried by an insulating disk supported by insulating guide pins mounted in said plate member, and a rod contact operable to extend within said chamber and abut said floating contact to bias the same into engagement with said butt contact in the closed circuit position.

7. A hi h tension circuit interrupter comprising adapter of conducting material, an explosion chamber member of strong insulating material, the wall of said member having a peripheral flange, a contact supporting fibre plate engaging one side of said flange and forming the upper side of the exlosion chamber, a contact carrying insulating disc depending from said plate, a clamping ring en aging the opposite side of said flange, and 0 ts coacting with said adapter and said ring for clamping the explosion chamber structure as a unit to said adapter. In witness whereof I have hereunto set my hand this 24th day of November, 1930.

WILLIAM H. TURNPENNY.

and explosion pot respectively, and a movcontact extending within said chamber coacting with said pair of contacts.

A high tensioncircuit interrupter of the 

